Willson, Robert Wheeler, 1853-1922 · Boston, New York Ginn & company · leaf 148
orizon in latitude 28° in the fulldarkness of night, the sun being below the twilight limit. Example 36. What is the latest date at which we can see Siriusin the evening twilight in latitude 42°? Sirius is visible when the sun is about 10° below the horizon, andcannot be seen later than the day on… … 136 LABOEATOEY ASTEONOMY the place occupied by the sun on May 15, which is, therefore, therequired date. Example 37. Bet-ween what dates is the sun visible at midnightat the North Cape, in latitude 70° north? Eectifying the globe for 70° north and rotating the globe slowly,it is found that points…
Astronomy
Internet Archive · Cornell University Library · Public Domain Mark 1.0. Free to use for anything.
